Fuel surge and swirl pots
- Thread starter Jon Olds
- Start date
Thanks, guys
Ive not taken much interest in swirl pots before, but my rough plan is to get one made about 1 litre in volume and house it near the tank to minimise fuel line plumbing. Then add an extra HP pump to send it forward. Extra will spill back. I know of a co. that will make it to a drg.
Questions:
Is a litre enough?
Should the pump that fills the tank be a LP one to avoid cavitigation effects in the pot?
Is shape critical?
Is mounting point or height critical?
Ive not taken much interest in swirl pots before, but my rough plan is to get one made about 1 litre in volume and house it near the tank to minimise fuel line plumbing. Then add an extra HP pump to send it forward. Extra will spill back. I know of a co. that will make it to a drg.
Questions:
Is a litre enough?
Should the pump that fills the tank be a LP one to avoid cavitigation effects in the pot?
Is shape critical?
Is mounting point or height critical?
skiddusmarkus
Active Member
What I don't understand is why you need an extra pump for swirl pots.It's still only pumping the same amount of fuel except it now has to fill up an extra litre in the pot.Once it's full,why does it need any more pressure to carry on pumping the same amount of fuel.
Can't you just fit one after the fuel filter without an additional pump?
Can't you just fit one after the fuel filter without an additional pump?
As I understand it
The fuel surge problem is cause by the OEM pump inlet picking up air, rather than fuel, dueing hard cornering. Once its got air into the system, this is reflected straight thro onto the line pressure. A swirl pot keeps a constant head of fuel into the main (new) pump. The OEM one just fills the pot.
The fuel surge problem is cause by the OEM pump inlet picking up air, rather than fuel, dueing hard cornering. Once its got air into the system, this is reflected straight thro onto the line pressure. A swirl pot keeps a constant head of fuel into the main (new) pump. The OEM one just fills the pot.
Just to get my understanding right here. Isn't a swirl pot to take air out of the fuel going to the injectors ? And a surge tank is to do what it says on the tin and prevent fuel surge ?
And, as Jon say's, you need 2 pumps as one fills the surge tank and the other feeds fuel from the surge tank to the rest of the fuel system ?
And, as Jon say's, you need 2 pumps as one fills the surge tank and the other feeds fuel from the surge tank to the rest of the fuel system ?
skiddusmarkus
Active Member
Why can't the fuel just overflow from the pot into the rest of system.Gordon started explaining this to me at JAE but I've forgotten 
.
Would a surge tank not just act as a mini fuel tank which won't be subject to fuel starvation as it's always full?
.Would a surge tank not just act as a mini fuel tank which won't be subject to fuel starvation as it's always full?
O
Odin
Guest
It looks pretty easy to do really, Just bolt a surge tank to the boot floor from demon thieve's a few pipe's and a pump and job's a gooden :lol: .
rob
rob
skiddusmarkus
Active Member
I've already got a surge tank but don't fancy forking out for another pump(quel surprise :lol.I have a walbro 255,does that mean I have to get one that matches that flow?
.I have a walbro 255,does that mean I have to get one that matches that flow?
Thanks Guys.
Ive borrowed a mate's book and it says 1 litre should suffice. Didn't think Demon Tweeks would do one, so that's nice to know. Get 10% off using their motorsport club. The Evo one looks sexy, but heavy. I'm trying to keep as much weight at the rear as poss. The sunken pump looks like trouble to change between stages, if it faults.
Good question has been raised. If the std pump runs out of flow on a one pump system, will I need to uprate both? Probably, unless the transient full power demand doesn't drain the mini tank.
I had fuel surge on my rally golf and it only lasted a couple of seconds.
Still thinking about it.
Ive borrowed a mate's book and it says 1 litre should suffice. Didn't think Demon Tweeks would do one, so that's nice to know. Get 10% off using their motorsport club. The Evo one looks sexy, but heavy. I'm trying to keep as much weight at the rear as poss. The sunken pump looks like trouble to change between stages, if it faults.
Good question has been raised. If the std pump runs out of flow on a one pump system, will I need to uprate both? Probably, unless the transient full power demand doesn't drain the mini tank.
I had fuel surge on my rally golf and it only lasted a couple of seconds.
Still thinking about it.
Thanks
Beer cans are 440 and 500ml. Allowing for the volume taken by the submerged pump, and the fact that the submerged pump will not pick up from the bottom of the tank, my gut feel says it looks 2 small..
Also, has anybody measured the flow down the recirc line back to the tank on a std system. The main pump must supply injector fuel plus recirc fuel on a std system. I guess if we know these two flows at full power, then sizing the pot is much easier. Any figures available?
Beer cans are 440 and 500ml. Allowing for the volume taken by the submerged pump, and the fact that the submerged pump will not pick up from the bottom of the tank, my gut feel says it looks 2 small..
Also, has anybody measured the flow down the recirc line back to the tank on a std system. The main pump must supply injector fuel plus recirc fuel on a std system. I guess if we know these two flows at full power, then sizing the pot is much easier. Any figures available?
0
00sid
Guest
i have just had this problem, taking a corner realy quick and on the exit when i planted the loud pedal the engine died for a second.
would a second pickup on the other side of the tank sort this out?
would a second pickup on the other side of the tank sort this out?
jonesgti_r
New Member
Cant you get something that will fit around the fuel pickup and stop the fuel moving away from the pick up :?: